Engine mounting bracket help please

[stellaontap]

Hi all, and Merry Christmas.

I am prepping a LQ4 into a 1979 gmc dually (Camper Special) swap. I have ordered engine mounting brackets from Holley (part number BHS540) and associated hardware but the engine brackets do not fit my frame. The kit is for a C10. Is there a difference between C10 frames and C35 frames?

Anybody experience this? Any guys out there do a similar swap and what engine mounting hardware did you use? Maybe someone can give alternate part numbers for me so I can get back on track.

Thanks in advance

Eric